//2009/08/18 22:40:53
#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <queue>
#include <sstream>
#include <algorithm>

using namespace std;

class FixTheAverage
{
public:
    double add(vector <double> list, double target)
    {
		double sum = 0.0;
		for(int i=0; i<list.size(); i++) sum += list[i];
		return target * (list.size() + 1) - sum;
    }
};
